Embossing disc with back-filled characters

ABSTRACT

Mated punch and die discs manufactured from workable sheet material, with embossed characters backfilled to provide resistance to embossure collapse.

United States Patent Inventor James A. Fort Camp Mlddleberg Heights,Ohio Dec. 18, 1968 Aug. 31, 1971 Addressograph-lllultigraph CorporationCleveland, Ohio Appl. No, Filed Patented Assignee EMBOSSING DISC WITHBACK-FILLED CHARACTERS References Cited UNITED STATES PATENTS 5/1939Wiley 29/421 3/1942 Zipf 197/6.7 5/1942 Van Buren 618i. 197/6.7 8/1943Bull 101/28 UX 12/1960 Jerothe.. 101/31 5/1962 Souza.... 197/6.7 UX9/1966 Craig 197/6.7 10/1966 De Man 197/6.7 1/1967 Miller 197/6.712/1968 Norvelle 197/6.7

Primary Examiner-Edgar S. Burr Attorneys-Russell L. Root and Ray S. PyleABSTRACT: Mated punch and die discs manufactured from workable sheetmaterial, with embossed characters backfilled to provide resistance toembossure collapse.

PATENTE-[l M1631 197i 3.602137 SHEEI 1 or 2 32 "aw/ Z6 MA A. FORTE/1MP 5fpwl ATTORNEY EMBOSSING DISC WITH BACK-FILLED CHARACTERS BACKGROUND OFTHE INVENTION This invention relates generally to embossing devices, andmore particularly to disc utilized in embossing machines for embossingheavy plastic and aluminum alloy articles.

There have been many prior art proposals for embossing machinesutilizing many different types of embossing implemerits. For example,U.S. Pat. Nos. 2,973,853; 3,029,920; and 3,293,691 illustrate machineswhich utilize precision formed individually mounted punch and die sets.These machines work extremely well and provide rapid precision embossingof articles such as heavy plastic and aluminum alloy plates for formingprinting-type address plates and the like.

Both the machine and the punch and die sets are designed for highproduction and character precisionbeyond the needs for many users.

There are also relatively inexpensive small hand-operated machines whichare suitable for embossing characters on soft plastic ribbon. Thesemachines often employ a disc on which characters are formed and whichdisc is utilized to emboss the characters on the soft plastic ribbon.These machines nor-- mally are squeeze operated. The relatively softplastic material which is embossed by these machines is easy to deformand hence does not produce excessive wear or pressure on the disc.However, these machines are not suitable for embossing hard plastic oraluminum alloy of the type used for address plates. One reason is thatthey do not generate sufficient pres sure. Another is that the characterdiscs are not of sufficieni: strength and abrasion resistance torepeatedly emboss such heavy material without character deformation,rounding or cracking.

Address printing plates have been filled with plastic and/or braze in aneffort to extend their useful life, and range of material to beembossed. Such metal with backfill does not provide an acceptableembossing punch.

SUMMARY OF THE INVENTION An advantage of this invention is provided bymaking sheet steel available by an embossing step to perform as a punchtool for embossing plastic and aluminum sheets into printing plates.

According to the present invention, a disc is provided having characterforming punches that will coact with a disc having die members toprovide embossings; and which punches will not deform or crack uponrepeated embossing of hard plastic or aluminum plates of the typessuitable for printingtype address plates.

One of the principal features of this invention is the provision of adisc having radiating fingers which fingers are provided with raisedcharacter forming surfaces on one side and corresponding depressions onthe other. The depressions are filled with compression resistingmaterial to prevent collapse of the characters upon repeatedembossments. This invention also contemplates a method of manufacturingsuch discs.

These and other features and objects together with a fullerunderstanding of the invention may be had by reference to the followingdescription taken in conjunction with the drawings in which:

DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a blank suitablefor forming into a punch disc of this invention;

FIG. 2 and 3 are portions of discs in plan view showing successivestages of manufacture;

FIG. 43 is a plan view of the next successive stage of manu facturing;

FIG. 5 is a sectional view taken substantially along the planedesignated by the line 5-5 of FIG. 4;

FIG. 6 is a detailed sectional view, somewhat diagrammatic, showing theformation of a punch character in one of the fingers of the disc;

FIG. 7 is a partial plan view, on an enlarged scale from FIGS. 1 through4, of several fingers of a disc having punch characters formed thereon;

FIG. 8A is a sectional view taken substantially along the planedesignated by the line 88 of FIG. 7 before grinding;

FIG. 8B is a sectional view taken substantially along the planedesignated by the line M of FIG. 7 after grinding;

FIG. 9 is a plan view of a blank suitable for forming into a die discmember;

FIG. 10 is a plan view of the blank of FIG. 9' after initial formingoperations; 8-

FIG. ill is a sectional view taken substantially along the planedesignated by the line Ill-11! of FIG. 10;

FIG. 12 is a portion of the disc in plan view at a later stage offormation, after other forming operations have been carried out;

FIG. 13 is a detail view taken substantially along the plane designatedby the line 13-413 of FIG. 14 showing, somewhat diagrammatically, theformation of a die character in one of the fingers of the disc;

FIG. M is a plan view, on an enlarged scale, from figs. 9 through 12, ofa portion of the disc, showing characters formed in several of thefingers; and

FIG. 15 is a plan view of a portion of the finished disc, with diecharacters in the fingers thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENT Briefly, the present inventioncontemplates the provision of punch and die carrying discs, which aresuitable for performing embossing operations in which the characters onthe punch disc will not deform or crack during successive embossingoperations on hard plastic or alloy aluminum plates, such as are usedfor address printing plates. The embossing discs of this invention findparticular use in the device disclosed in copending application Ser. No.784,557 filed Dec. 18, 1968, entitled, Embossing Device.

The device disclosed in said copending application utilizes a pair ofembossing discs one of which has punch members, and one of which has diemembers. The discs are normally maintained in spaced relationship androtatabie together to move a selected punch and die set to an embossingstation. At the embossing station the article to be embossed is securedbetween the punch and die discs, and the discs are moved together andpressure applied to the corresponding punch and dies to perform anembossing operation on the article to be embossed. Although the presentinvention finds particular use in the device described in said copendingapplication, it is to be understood that its use is not limited thereto.it can be utilized in other embossing machines wherein embossingoperations are performed repeatedly and where resistance to deformationand cracking of the punch is desirable or necessary.

Referring now to the drawings, FIGS. 1 through 88 show successive stagesof manufacture of an. embossing disc punch made according to thisinvention. FIG. 1 shows a blank 10 from which the disc carrying thepunch members is formed. Preferably the blank is low or medium carbonsteel, e.g. AISI 1070, in the annealed condition. Normally, the disc 10will require mounting, tooling and indexing holes. Therefore, a centralmounting aperture 12 is punched together with a plurality of toolingholes 14, and an indexing, or aligning hole 16. The specific selectionand location of the various holes shown is for a disc adapted to be usedin said copending application Ser. No. 784,557 and as such illustrateshow various holes are first provided. Other applications may welldictate other types or locations of holes.

Refer to FIG. 2. After the holes 12, M, and 16 have been punched, aplurality of teardrop-shaped slots 18 are punched. The slots 18terminate short of the outer edge 20 of the disc 10. Next, the outer rimof material is trimmed from the blank 10 as shown in FIG. 3, so as toleave the disc with a central portion 22 having a plurality of fingers24% extending therefrom.

Following the trimming, the end of each of the fingers 24 is bent to anL-shaped configuration, as shown in FIGS. 4 and 5, to provide acharacter receiving end 26 at the outer extremity of each of the fingers24. The character receiving ends 26 are generally parallel to, but on aplane spaced from, the plane of the fingers 24.

Once the character receiving ends 26 have been formed, they are thenready to have formed therein the characters which will be used forembossing. The formation of one of the characters is shown somewhatschematically in FIG. 6. A master punch P and a master die D are shown,positioned on opposite sides of the character receiving end 26 of one ofthe fingers 24. The master punch and die are each precision formed andheat treated tools, which are relatively massive and are adapted to formthe desired character in the finger of the disc, by actually embossingthe character itself in the character receiving end 26. When the masterpunch and master die are squeezed together, with the character receivingend 26 therebetween, the desired character will be formed by raising thedesired surface configuration 28 on one side of the character receivingend 26 leaving a corresponding depression 30 on the other side.

Each of the fingers is formed with a separate character having theraised portion on one side and the corresponding depression on theopposite side. The raised portions of the characters then become thecharacter forming punches which, in cooperation with correspondingmating die members, can be used to emboss characters on the desiredarticle in the embossing machine.

As far as character formation is. concerned, low or medium carbon steel,in the annealed condition, is preferred because it is relatively easy toform the characters therein, by the use of master punch and die sets.However, when punch members, formed of such steel in the annealedcondition are used for embossing hard plastic and aluminum alloy platestherewith, the characters collapse after relatively few embossings.

Metallurgical experience would suggest that to overcome the tendency ofthe characters to collapse, the discs should be heat treated to hardenthe steel. However, heat treatment of this medium carbon steel to thehardness required to resist collapse, causes the punch characters tocrack upon repeated embossing operations on hard plastic and aluminumplates.

The use of an inherently tougher material, such as alloy steel, for thepunch discs, in which the punch characters are formed, results in poorlyformed characters and excessive wear on the master punch and die used toform the punch characters. Therefore, such harder material is notsatisfactory for punch discs.

It has been discovered that in order to utilize the low or medium carbonsteel, resistance to character collapse during the repeated embossingmay be achieved by a compression resistant filler material 32 depositedon the rear surface of the character receiving ends 26, filling thedepressions 30 in the back of the characters. Any one of several typesof filler material may be employed; for example, brazing alloys per formespecially well in preventing character collapse. Tests conducted onpunch members, formed of medium carbon steel filled with brazing alloy,withstood over 30,000 embossings, and were also able to embosssatisfactorily on aluminum plates. Brazing alloys can be convenientlyapplied in the form of a brazing paste. After the paste has beenapplied, the fingers are heated to cause the alloy to fuse.

Another type of filler material that may be used is epoxy resinimpregnated with iron powder. Epoxy resin filler is satisfactory forpunches used for embossing hard plastic plates, but it does tend tobreak down and allow character collapse on punches used for embossingaluminum alloy plates.

Normally, the filler material will be mounded up in a somewhat roundedshape, as shown in FIG. 8A. Since this surface is a backing surface forthe punch, and bears against a pressure surface, it should be groundoff, as shown in FIG. 88, so that it is flush with the surface of theend 26.

When filler material is used, it is desirable to heattreat the discmaterial, where it is formed into punches, to enhance its characterforming characteristics. This is done, either before or after theapplication of the filler material, depending upon what filler materialis utilized. If the tiller material is a room temperature curing epoxyor other low-temperature curing material, then the heat treatment shouldbe applied before the filler material is deposited. On the other hand,if the filler material is a brazing alloy, or other material whichrequires high temperatures for fusion, the heat treatment should be doneafter the application of these materials. By heattreating after filling,the results of the heat treatment will not be removed by the temperatureto which the disc is subjected to melt the brazing material. In anyevent, a hardening and tempering operation is desired, which will raisethe hardness sufficiently to increase the resistance of the punchmaterial to abrading and rounding but not hard enough to producecracking upon repeated embossing operations. In the case of mediumcarbon steel, such as AISI 1070 grade, the material can be hardened andtempered to a Rockwell C hardness of between 44 and 47. This provides astronger material to resist rounding and abrading, but the material isnot brittle enough to crack upon repeated embossings.

Thus, by providing a disc material which can be relatively easily formedto the desired punch characters, and, by filling the back of the punchcharacters with filler material to prevent collapsing, a satisfactorydisc, with punches formed thereon, is provided, which is readily formedand which will perform adequately under repeated embossing operations.

The punch disc of this invention is adapted to be utilized on anembossing device with. a die disc having die members formed to mate withthe punch members. FIGS. 9 through 15 show the various steps involved inmaking a die disc suitable for use in conjunction with the punch disc ofthis invention.

In forming the die members, a blank 40 is provided from which the disccarrying the die members is to be formed. The blank 40 is preferably amedium carbon steel, but an alloy steel may also be used, since, as willbe explained presently, the dies are formed by a coining or sinkingoperation rather than an embossing operation, as with the punch disc.

The disc 40 has a central opening 42, holes 44, and an indexing opening46 punched therein.' The disc 40 is then machined to provide a steppedhub section 48, and an annular raised ring section 50 near an outer edge52, as can be seen in FIGS. 10 and l l.

A plurality of teardrop shaped slots 54, similar in configuration tothose formed in the punching blank 10, are provided, which extend pastthe annular ring 50, but do not extend to the outer rim 52. Thisconfiguration, as shown in FIG. 12, provides a plurality ofinterconnected fingers, each with a raised portion 50', the raisedportions 50 constituting segments of the annular ring 50. Each of theseraised portions 50' is adapted to have formed therein a female or diecharacter.

The formation of a character is shown schematically in FIG.

" 13. In this formation of a character, a master punch P is provided,having formed thereon the desired character. The punch is utilized inconjunction with a backing member B, and the punch P, in conjunctionwith the backing member B, is sued to sink the desired character in theraised portion 50. This is in the nature of a coining or die sinkingoperation, with the cavity being formed in the metal. This coiningoperation utilizes only a master punch and not both a master punch and amaster die, as in the case of the formation of the punch characters.This type coining operation, therefore, is much less severe on theforming tools and, hence, a tougher material, such as alloy steel can beused for the die disc. A segment of the disc having the die charactersformed therein is shown in fig. 14.

After all of the die characters have been formed, in the raisedportions, the outer rim is trimmed so as to define a die disc having acentral portion 56 from which a plurality of fingers 58 radiate, each ofthe fingers carrying a raised portion 50' in which the selected diecharacters are formed, as shown in FIG. 15.

The die disc thus formed, is adapted for sue in conjunction with thepunch disc previously described. This description is merely illustrativeof one type of die disc, and its method of manufacture, which can beutilized in conjunction with the punch disc, it being understood thatother types of discs and other methods of manufacturing may be employedin other circumstances.

Whereas the present invention has been shown and described herein inwhat is conceived to be the best mode contemplated, it is recognizedthat departures may be made therefrom within the scope of the inventionwhich is, therefore, not to be limited to the details disclosed herein,but is to be afforded the full scope of the invention as hereinafterclaimed. 7

I claim:

1. An embossing disc couple, each disc having a plurality of fingersradiating from a central section;

one of said discs being a punch disc formed of carbon steel withcharacter punch members formed in said fingers, each punch member havinga raised surface on one side of the finger and a correspondingdepression on the other side, each said raised surface beingsufficiently soft to resist cracking upon embossing operations andinherently collapsible into the depressions upon application ofembossing pressure, and compression resisting material disposed in saiddepression to prevent collapse of said raised surface into thedepression;

the other of said discs being a die disc with intaglio surfaces formedto cooperate with the raised punch member surfaces in bending and slightcoining of sheet plastic and soft metals suitable for printing plates;

whereby, said disc couple is closeable and subject to application oflocal pressure for embossing operations without collapse of said punchmembers.

2. The invention as defined in claim 1, wherein said compressionresisting material includes an epoxy resin.

3. The invention as defined in claim I, wherein the compressionresisting material is a metal having a melting point lower than saidsteel.

4. The invention as defined in claim 1., wherein said steel has aRockwell C hardness of between 44 and 47.

5. The invention as defined in claim 1, wherein said compressionresisting material is flush with the surface of the finger.

1. An embossing disc couple, each disc having a plurality of fingersradiating from a central section; one of said discs being a punch discformed of carbon steel with character punch members formed in saidfingers, each punch member having a raised surface on one side of thefinger and a corresponding depression on the other side, each saidraised surface being sufficiently soft to resist cracking upon embossingoperations and inherently collapsible into the depressions uponapplication of embossing pressure, and compression resisting materialdisposed in said depression to prevent collapse of said raised surfaceinto the depression; the other of said discs being a die disc withintaglio surfaces formed to cooperate with the raised punch membersurfaces in bending and slight coining of sheet plastic and soft metalssuitable for printing plates; whereby, said disc couple is closeable andsubject to application of local pressure for embossing operationswithout collapse of said punch members.
 2. The invention as defined inclaim 1, wherein said compression resisting material includes an epoxyresin.
 3. The invention as defined in claim 1, wherein the compressionresisting material is a metal having a melting point lower than saidsteel.
 4. The invention as defined in claim 1, wherein said steel has aRockwell C hardness of between 44 and
 47. 5. The invention as defined inclaim 1, wherein said compression resisting material is flush with thesurface of the finger.